package day4;

/**
 * @author oldliu
 * @since 1.0
 */
public class CTest {
    public static void main(String[] args) {
        //堆和栈
        Circle c=new Circle();
        c.radius=10;
        c.x=3;
        c.y=20;
        double a = c.area();
        System.out.println("面积是 "+a);
    }
}
